Cinder pot



A. D DAVIES CINDER POT March 28, 1939.

Filed May 14, 1938 Patented Mar. 28, 1939 UNITED STATES PATENT OFFICE 4 Claims.

' fore but in all such pots, known to me, the side wall was of substantially the shape of a sinusoid curve insection and of uniform thickness from the top to the bottom of the pot to provide what may be termed longitudinal corrugations.

These corrugations formed, in effect, a side wall made up of a series of alternate peaks and valleys. It has been found that where such corrugated pots are in use and filled with molten slag the valleys become visibly hot and are of a substantially cherry or dull red color in appearance,

,while the peaks remain substantially grey in color, and I believe that this is due to the fact that the area of the heat absorbing surfaces opposite the valleys is greater than the area of the heat radiating surfaces of the valleys on the outside of the 1. 1;, while at the peaks the reverse is true since the heat radiating surfaces of the peaks are considerably greater than the heat absorbing surfaces on the inside of the pot and opposite such peaks.

Inspection of the corrugated pots now in service discloses that the intense heat to which the pots are subjected, and especially that portion opposite the valleys of such pots, tends to cause the metal to disintegrate and, as a result, fire cracks, which reduce the life of the pot, invariably occur along the ridges on the inside of the pot directly opposite the valleys in the outer surface thereof.

One object of the present invention is to provide a cinder pot having a side wall of irregular shape in section in which the area of the heat absorbing surfaces at any point in the side wall is substantially equal to the heat radiating surfaces at that point, and I accomplish this object by providing a side wall having a series of substantially channel-shaped sections therein, which taper both in width and depth from the rim toward the bottom of the pot.

Another object of this invention is to provide a cinder pot having a side wall provided with a series of channel sections of substantially channel-shape and in which the legs of the channel sections are substantially radially disposed and act as stiffening ribs or beams for the side wall of the pot.

A further object is to provide a cinder pot having a flexible side wall free to expand and contract, which is of varied thickness, the greatest thickness being at or near that portion of the wall which is subject to the greatest heat when the pot, is in use to thereby reduce disintegration of the metal due to fire cracking and thereby increase the life of the pot.

These and other objects which will hereinafter be made apparent to those skilled in this particular art are accomplished by means of this invention, one embodiment of which is described in the following specification and illustrated in the accompanying drawing, in which:

Figure 1 is a top plan view of a pot made in accordance with my invention; 15

Fig. 2 is a sectional view taken on the line II--II of Fig. 1;

Fig. 3 is a view in side elevation of the pot;

Fig. 4 is an enlarged detail view illustrating the construction of the side wall; 20

Fig. 5 is a partial plan view of another exemplification of my invention; and

Fig. 6 is a sectional view taken on the line VIIL-VIII of Fig. 5.

In Figs. 1 and 4 of the drawing, a cinder pot Ill is shown having a bottom ll of substantially spheroidal shape and aside wall l2 extending upwardly and outwardly from the bottom II, which is made in accordance with my invention and designed to withstand bulging and disintegration of the metal due to fire cracking. The side wall I2 is made up of a series of circumferentially spaced substantially channel-shaped sections 13 which extend from the rim to the bottom of the pot, with the legs I4 of the channel sections l3 extending outwardly and connected together at their outer ends by wall portions I5. The channel sections l3 taper both in width and depth from the top toward the bottom of the pot in and the legs M, which act as stiffening beams or ribs for, the pot, extend beyond the tangent point between the side wall and the spheroidal bottom I I and merge with the bottom H at a point beyond such tangent point, to increase the flexibility of the spheroidal bottom to better resist the strains of expansion and contraction. The ribs M are substantially radial of the potand the surfaces thereof, which are inside the pot, are flared outwardly andvfilleted to the inner portions of the surfaces l5 of the side 50 walls, so as to provide recesses l6 between the channel sections which are somewhat wider at their mouth than they are at the bottom.

With this construction, it is apparent that pots made in accordance with my invention, may be 55 readily emptied although the slag or cinder cast therein has solidified and a shell has been formed adjacent the inner surface of the pot, of the same shape in section as the inner surface of the pot, because in my construction the recesses or spaces between adjacent channel sections are wider at their mouth than at the bottom thereof and, consequently, binding of the shell within the pot is eliminated.

A pot constructed as herein described is he:- ible from the standpoint of thermal expansion and contraction for the reason that the bottom being spheroidal in shape embodies the thermoexpansive flexible properties of a sphere and the channel sections ll permit the wall of the pot to freely expand and contract circumferentially with changes in temperature.

Since the channel sections increase both in depth and width from the bottom to the rim of the pot, the actual circumferential length of the wall section at successive horizontal elevations increases at successively greater rates than the change in diameter and, as a result, the pot will not develop bulges and cracks as a result of repeated and severe temperature changes.

It should be noted that in a pot constructed in accordance with my invention and having substantially channel-shaped sections therein, the heat radiating surfaces of the pot are substantially equal to the heat absorbing surfaces thereof. That is to say, the space A between the channel sections it on the inside of the pot ,which absorbs the heat from the molten slag poured therein is somewhat less than the area of the heat radiating portion A of the surface I! on the outside of the pot; the area of the heat absorbing surface of the base of the channel section marked 8" is somewhat less than the area of the heat radiating surface B on the outside of the pot, and the area of the heat absorbing surfaces C of the legs H on the inside of the pot is substantially equal to the area of heat radiating surfaces C of the legs ll on the outside of the pot. Consequentiy, the heat absorbing surfaces of the pot are all substantially equal to but not greater than the heat radiating surfaces thereof and the strains ordinarily set up in a pot as a result of uneven heating of the various sections thereof are eliminated in a pot made in accordance with my invention.

In order to prevent disintegration of the metal in the side wall If, due to fire cracking and the like, the wall I! is of varying thickness and increases in thickness from the bottom to a point I! adjacent or slightly above the trunnion ring, which actual tests show to be the hottest part of the pot, and then decreases from that point to the original thickness at the rim of the pot, and I prefer that the wall at the point I! be approximately 40% thicker than the thickness of the wall at the bottom and rim portions thereof.

From the foregoing description, it is apparent that the legs ll of the channel-shaped channel sections I! of my improved pot act as stiffening beams or ribs and, consequently; my pot is of substantially greater strength than a wall of any other shape having the same weight or thickness.

The pot I0 is of the type designed and primarilyused for slag cars and buggies, and for this purpose support pads or lugs are spaced uniformly around the pot and located at or slightly above the middle thereof for supporting the pot on the trunnion ring of a car or buggy (none shown) in the usual manner. which comprise a horizontal section it apertured The support pads,

auras to receive a supporting bolt and two vertical rib portions ii, are formed on the surfaces Hi between the channelsections l3 and not only strengthen this portion of the pot but also facilitate the casting of the pot.

When a pot of the character herein described is in use, it frequently happens that the molten slag is permitted to solidify therein before the pot is emptied. As the slag solidifies. a shell is formed around the inside surface of the pot which becomes thicker and thicker as the cooling increases, and with my pot, since the inner surfaces of the ribs are spaced wider at the mouth of the recesses than at the inner portion, this shell may be readily removed without binding within the recesses.

7 Figs. 5 and 6 illustrate another exemplification of my invention in which the side wall lib of the pot is provided with circumferentially spaced inwardly projecting channel sections li In this exempliflcation, however, the thickness of the side walls varies both circumferentially and longitudinally i. e., the base portions of the sections are of substantially greater thickness than the remaining portions of the side wall, to increase the side wall thickness at the hottest points of the pot and to decrease disintegration of the metal due to fire cracking and, consequently, increase the life of the pot. In this modification, the base I30 of each channel section lib is thickest at the upper end thereof and decreases in thickness from the top of the pot to the bottom where they are of the same thickness as the remainder of the side wall.

From the foregoing description of my invention, it is apparent that I have produced a cinder not having a flexible side wall in which the heat absorbtion area is somewhat less than (never greater than) the area of the heat radiating surface and that, as a result, all parts of the pot are subjected when in use to the same conditions and disintegration of the pot, due to localized temperature strains, is thereby eliminated.

It is further apparent that the shape of the channel sections of my improved pot gives a stronger side wall than a corrugated wall of the same weight and thickness, and that my improved wall design is much stronger than the ordinary uncorrugated or circular pots now in general use.

While I have described one embodiment of my invention, it is to be understood that certain changes, additions, subtractions and omissions may be made therein without departing from the spirit of my invention or the scope of the appended claims.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

l. A cinder pot for receiving molten slag and the like having a closed spheroidal bottom and an upwardly diverging side wall, the said side wall being of increased thickness intermediate its top and bottom and being provided with a series of circumferentially spaced tapered substantially fiat-bottomed channel-shaped sections provided with legs connecting adjacent sections together.

2. A cinder pot for receiving molten slag and the like having a closed shperoidal bottom and an upwardly diverging side wall, the said side wall increasing gradually in thickness from a point adjacent the bottom to a point corresponding substantially to that portion of the not which becomes hottest and thereafter decreasing gradually in thickness to the rim of the pot and being provided with a series of circumferentially spaced tapered substantially fiat-bottomed channelshaped sections terminating below the point of tangency between said wall and said bottom, legs being provided to connect adjacent sections together.

3. A cinder pot for receiving molten slag and the like having a closed spheroidal bottom and an upwardly diverging side wall, the said side wall being of increased thickness intermediate its top and bottom and being provided with a series of circumferentially spaced tapered substantially fiat-bottomed channel-shaped sections provided with legs connecting adjacent sections together,

and bottom and being provided with a series of circumferentially spaced tapered substantially fiat-bottomed channel-shaped sections provided with legs connecting adjacent sections together, the construction and arrangement being such that the said side wall alternately increases and decreases in thickness circumferentially.

ARCHIBALD D. DAVIES.

CERTIFICATE OF CORRECTION.

Patent No. 2,152,2 5.

- ARCHIBALD D.

DAVIES March 2 19 9.

It is hereby certified that error appears in the specification of the above numbered patent requiring correction as follcit'm; Page 1, second column, line 21 for "VI-II VIII" read VI-VI; and that the said Letters Patent shouldbe read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 6th day of June, A. D. 1959.

(Seal) Henry Van Arsdale Acting Commissioner of Patents. 

